Improvement in vault-lights



l. WOOD.

Vault-Lights.

N0. 138,724. PatentedMay 6,1873.

WITNESSES v INVENTOR.

UNITED STATES PATENT OEEIoE.

JOHN WOOD, OF NEW YORK, N. Y.

IMPROVEMENT lN VAULT-LIGHTS.

Specification forming part of Letters Patent No. 138,724, dated May 6, 1873; application filed November 26, 1872.

To all whom it may concern:

Be it known that I, JOHN Wool), of the city, county, and State of New York, have invented certain Improvements in Vault-Lights, of which the following is a specification:

Nature and Object.

This invention belongs to that class of articles known as vault-lights, or in which tiles or bulbs of glass are inserted in iron frames or plates to cover vaults or chambers under the streets or pavements of cities 5 and this improvement consists in forming the glass bulb with a projecting flange to support a packing and confine the same in place, and form a tight joint between the bulb and its iron plate.

Drawing.

Figure 1 is a plan of a portion of an iron plate provided with the glass tiles. Figs. 2, 3, and 4 are end Views of the tile or bulb to illustrate how they may be conveniently made for being turned by a screwdriver, key, or wrench. Fig. 5 is a sectional view of the plate with a glass bulb or tile inserted therein.

A represents the tile or glass bulb, one end of which may be provided with holes, as at Fig. 2, in which to insert a key for the purpose of screwing it into the plate B, which is provided with holes and threads to correspond with the shape of the glass bulb; or a slot, as

at Fig. 3, may be made in the end of the tile, in which a screw-driver may be used; or the edges of the flange may be formed, as shown at Fig. 4, with flattened surfaces so that a wrench may be used for turning it into position in the plates. To make the joint between the iron and the glass Water-tight to prevent leakage into the vault, a gasket otl r u bb er or lead, orsome other packing is inserted between the flange of the glass and the plate of metal, as shown in Fig. 5.

The glass tiles or bulbs being inserted from below, as shown at Fig. 5, the screw-threads will hold them in position in the plates, and the now very annoying objection of bouncing out of their recesses will be avoided.

I do not broadly claim a glass bulb having screw-threads for fitting or screwing into vaultlights, as such is not my invention.

Claim.

I claim- The bulb A formed with the packing -supporting flange, as shown, and with external screw'threads for operation in connection with the plate A, as and for the purpose specified.

' JOHN WOOD.

Witnesses:

E. V. ELIOT, BOYD ELIOT. 

